1. Field of the Invention
Embodiments of the present invention generally relate to enhancing the lifetime of a micro-electromechanical system (MEMS) device.
2. Description of the Related Art
Digital variable capacitors (DVCs) utilizing MEMS technology operate by having a switching element of the MEMS device move between a state of high capacitance and a state of low capacitance. In a state of high capacitance, the switching element is in a position adjacent an RF electrode. In a state of low capacitance, the switching element is in a position adjacent to another electrode spaced from the RF electrode, or more specifically, away from an insulating layer that is disposed on the RF electrode. The switching element may also be moved to ground whereby the switching element is adjacent neither the RF electrode nor the other electrode.
During the lifetime of the MEMS device, the switching element cycles between the various states (i.e., high capacitance, low capacitance and ground). For a cycle, the switching element moves from the ground state to either the high or low capacitance state. After the cycle is completed, and before the next cycle, the switching element returns to the ground state. Then, a new cycle begins whereby the switching element moves to either a high or low capacitance state, or remains in the ground state.
There are only a finite number of times that the switching element can move before the MEMS device fails due to the structural integrity of the switching element. With each movement of the switching element, the MEMS device is closer to failure. There is a need in the art for increasing the lifetime of MEMS devices in DVCs.